한국정밀공학회지 (Journal of the Korean Society for Precision Engineering)

  • 제30권12호
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  • Pages.1295-1301
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  • 2013
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  • 1225-9071(pISSN)
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  • 2287-8769(eISSN)
한국정밀공학회 (Korean Society for Precision Engineering)
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사출성형 해석을 통한 Weldline 및 Flow mark 개선사례

The Improvement of Weldline and Flow mark Defection by using Injection Molding Analysis

  • 투고 : 2013.10.01
  • 심사 : 2013.11.20
  • 발행 : 2013.12.01
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초록

The cause of flow mark defect is known as non-uniform temperature of mold surface when the flow front meets the cold cavity. The exact definition and classification of Flow mark is not clear because the mechanism of flow mark is not figured out till now. Any injection molding analysis software can not predict the flow mark phenomena. To solve weldline and flow mark defects, the gate thickness is reduced to increase the melt front velocity and the melt front velocity of the flow mark area is increased from 82.3mm/s to 104.7mm/s. In addition, the bulk temperature of the flow mark area is increased from $178.3^{\circ}C$to $215.2^{\circ}C$ by adding a cold slug well. The flow mark phenomena can be greatly reduced by increasing the flow front velocity and elevating the bulk temperature.

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참고문헌

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